-duck-ham



(No fiddel.) 2 Sheets-Sheet 2. F. E.-DUGKHAM. PNEUMATIC GRAIN OONVBYER. No. 522,458. Patented July 3, 1894.

WITNESSES. IN YEA/TOR I JGQQW ATTORNEYS "m: NORRIS screws 00.. PNOTO-UTNQ WASHINGWJNL a. c

,cillating two-chambered air-lock delivery box.

' U ITED STATES PATENT, QFFICE. p

FREDERIO ELIOT DUOKHAM, OF LONDON, ENGLAND.

PN EU MATlC G RAlN-C ONVE'YER.

SPECIFICATION forming part of Letters Patent No. 522,458, dated July 3, 1894.

Application filed December 14,1893. Serial No. 493,698.

.To. all whom it may concern:

Be it known that I, FREDERIO ELIOT DUCK- HAM, civil engineer, of Millwall Docks, London, England, have invented new and useful Improvementsin Pneumatic Grain-Conveyors, (for which I have obtained Letters Patent in the following country, namely: British India, dated October 28, 1893, No. i 263,) of which the following is a full, clear, and exact description.

My invention relates to apparatus for loading, unloading, and transferring, from one place to another, grain and other granular or pulverulent matters in bulk by pneumatic agency and the invention has for its obj dot to enable the methods of working by exhaustion and by compression of the air to be combined or applied the one' in continuation of the other.

Pneumatic apparatus such as that to which my present improvement relates, is described in previous Letters Patent of theUnited States of America, dated the 8th day of March, 1892, No. 470,555, and in an improved form in another application for Letters Patent, of even date herewith, Serial No. 493,696. Such apparatus when used for loading and unloading ships cargoes is generally arranged on a barge or on the quay and it has heretofore only been capable of delivering below the level of the osj When, therefore, in discharging a vessel it is required to deliver in awarehouse or elsewhere at a height above, or distance from, the airlock delivery box it has been usually necessary to employ other means of conveyance to such further height or distance. Again in loading a shipfrom'barges, since the same apparatus is used both for loading and unloading, the air lock delivery boxes cannot be conveniently placed at a great height, and it has been necessary to employ additional means, such as bucket elevators, to raise the grain,&c., from the point at which it is delivered by the pneumatic apparatus to a height which will enable it to fiow through the vesselshatchway into the hold.

' Thepresentimprovement consists in the combination, with the oscillating two-chambered airlock delivery boxes of pneumatic apparatusworking by exhaustion, of means whereby the further conveyance of the mat- (No modehl Patented in India October 28, 1893, N0. 263.

ters delivered thereby is effected by 21. current of ,air under pressure, the, said means comprising a closed chamber into which the air lock delivery box discharges, supplied with air under pressure and containing a noz; zle with air-supply sleeve immersed in the contents of the chamber and connected to a pipe leading to the point of denately tothe one or other of the twin chambers G C of the air lock delivery box, oscillating on a horizontal axis D under the control of l counterweighted detent mechanism I, the communication with the hopper A and with. by-pass air passages G G connected by pipes H H with the upper part of the hopper, being effected through apertures c c in a valve face E on the air-lock deliver'y box, moved by the oscillation of the delivery box beneath a valve seat surrounding the mouth of the hopper A and furnished with by-pass ports 9 g, all as described in my other application of even date herewith.

I K is a closed hopper-shaped chamber into which the chambers O O of the air-lock delivery box discharge and into which the air that was drawn 0E from A by the exhausting engine (or air from a special blowing engine) is forced through pipe L. The chambers C C communicate alternately with chamber K by discharge apertures m m in valve faces M M which work over oorrespondingvalve seats N N on pipes O O leading'to chamber K, the valve faces being curved to an arc struck from axis D and being soarranged that the outlets from chambers O O. and the inlets to the chamber K are always closed to and the chamber K the equilibrium of pressure necessary to permit the rapid flow of the matters to be delivered from the one to the other, passages P P, connected by a pipe P with chamber K, communicate at the proper moment, through ports 19 p in the seat of the valve E, with the aperture 0 or c of the chamhers O O.

\Vithin the lower part of chamber K is fixed a nozzle R which leads out from the chamber Kand is connected to a conveying pipe b leading to the point where the grain, &c., is to be discharged. The nozzle R is surrounded by a sleeve T of sufiiciently larger dlameter to provide an annular air passage between the nozzle and sleeve, the nozzle and sleeve being immersed in the grain, &c., contamed in chamber K and the open upper end of the sleeve rising above the level thereof, inorder to admit of the air forced into the upper part of chamber K through a pipe L connected with the delivery orifice of the exhausting engine, so that the engine works both as an exhauster and air compressor, the air thereby supplied to chamber K passing down the sleeve and carrying along with it into the nozzle R the grain, &G., as it flows down below the sleeve T. The lower end of the sleeve terminates at a certain height above the lower end of the nozzle such that a certam depth of grain, 850., will always be thus interposed in the path of the air current. Theexact relative position of the sleeve and nozzle is subject to slight variation, according to the nature or condition of the grain or other matters to be conveyed, the height or distance towhich it is to be conveyed, the

air pressure available, and other circumstances, the efleot of varying the height of the mouth of the sleeve being to vary the relative proportion of the air current to the matters carried. To enable this adjustment to be made the lower part of the nozzle as at r F1g. 1 or of the sleeve as attin Fig. 2 is fitted to sllde telescopically on the main part thereof and is adjusted by any convenient means, such, for example, as a screw rod r and nut r as shown in Fig. l or a forked lever t pivoted to the adjustable partt and working on a fulcrum in the vertical side of the chamber and operated by an adjusting lever t outside the chamber. If it should not be required to convey the grain, &c., to a further point it may be delivered directly from the chamber K by opening a slide K at the bottom thereof.

Referring to Fig. 2 in which the same letters indicate the same parts as in Fig. 1, the operation is precisely the same as that above described, the only structural dilference belng that the chamber K wholly incloses the air lock delivery boxes 0 C and its counterweight mechanism; Consequently the valves M M and seats N N are not required, the outlets of the chambers G 0' being closed by hinged flap valves, as usual, closing under external air pressure and opening under the weight of the contents of the chamber when equilibrium of pressure is established by the inlet orifices c c of the chambers C 0' opening to the ports 1) p, which, as in the other case, are in communication with chamber K.

I claim 1. The combination, with the oscillating two-chambered air-lock delivery box having a valve-like connection with an exhausted charging hopper, of a closed chamber supplied with air under pressure and into which the chambers of the air lock delivery box are adapted to discharge, and a valve at the upper part of the airlock delivery box establishing equilibrium of pressure between the said chamber and the chambers of the delivery box only at the moment of their discharge, substantially as specified.

2. The combination, with the oscillating two-chambered air-lock delivery box having a valve-like connection with an exhausted charging hopper, of a closed chamber supplied with air under pressure and into which the chambers of the air-lock delivery box are adapted to discharge, and a valve at the up per part of the air-lock delivery box establishing equilibrium of pressure between the said chamber and the chambers of the deliv' ery box only at the moment of their discharge, and a dipping nozzle within said chamber connected to a delivery pipe andsurrounded by an air sleeve rising above the grain, &c., contained in the chamber inwhich both the sleeve and nozzle are immersed, substantially as specified.

3. The combination, with the oscillating twochambered air-lock delivery box having valvelike connection with an exhausted charging hopper, of a closed chamber supplied with air under pressure, and of valves establishing communication at the required times between the closed chamber and the lower parts of the chambers of the air-lock delivery box at the same timethat another valve establishes communication between the said chamber and the upper part of the said chambers of the air-lock: delivery box, the valves controlling the communications of the air-lock delivery box with the charging hopper and with the closed chamber into which the air-lock delivery box discharges, being all operated by the oscillation of the delivery 1 box under the weight of the load and under 3 the control of counterweighted detent mechlanism, as specified.

t. The combination, with a closed chamber supplied with air under pressure and into 1 which the air-lock delivery box of pneumatic conveying apparatus working by exhaustion jdischarges, of a clipping nozzle within said lchamber connected to a delivery pipe and lsurround'ed by an air sleeve rising above the l grain, &:c., in said chamber, inwhich both the lsleeve and nozzle are immersed, the depth of immersion of the sleeve being so much less than that of the nozzle that the grain, 850., will flow beneath the sleeve into the path of the air current, as specified.

5. The combination, with a closed chamber supplied with air under pressure and into which the air-lock delivery box of pneumatic conveying apparatus working by exhaustion discharges, of a dipping nozzle within said chamber connected to a delivery pipe and surrounded by an air sleeve rising above the grain, &c., in said chamber, the sleeve being made in two lengths whereof the lower one is fitted to slide telescopically, and means for adjusting the height of the sliding part of the sleeve relatively to the month of the nozzle, substantially as specified.

6. A combined pneumatic conveying apparatus working partly b yexhaustion and partly by compression for conveying the same matters by the same current of air beyond the point to which they are conveyed by exhaustion, which consists of an oscillating air-lock HAM.

FREDERIC ELIOT DUCKHAM. In presence of G. F. WARREN, 17Z Gracechurch Street, London, Notary Pub,-

T.' WI KENNARD, Clerk to A. III. &' Wm. Clark, Patent Agents,

53 Chancery Lane, London. 

